HYL1 controls the miR156-mediated juvenile phase of vegetative growth.
J Exp Bot
; 63(7): 2787-98, 2012 Apr.
Article
em En
| MEDLINE
| ID: mdl-22268150
ABSTRACT
HYL1 is an important regulator of microRNA (miRNA) biogenesis. A loss-of-function mutation of HYL1 causes the reduced accumulation of some miRNAs but fails to display the miRNA-deficient phenotypes of these miRNAs. In Arabidopsis, miR156 mediates phase transition through repression of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE (SPL) genes. However, it remains unknown whether, and if so how, HYL1 enables phase transition through miR156. This study showed that a loss-of-function mutation of the HYL1 gene caused defects in the timing of the juvenile phase. In the primary leaves of hyl1-2 mutants, abaxial trichomes were generated prematurely, the leaf blades elongated, and the blade base angles enlarged, as is observed for adult leaves. In hyl1-2 p35SmiR156a and hyl1-2 spl9-4 spl15-1 plants, increased accumulation of miR156a and repressed expression of the SPL genes were concomitant with a complete or partial rescue of the hyl1-2 phenotype in phase defects. In contrast, overexpression of the SPL9 gene in hyl1-2 mutants led to total disappearance of the juvenile phase. Moreover, HYL1 prevented the premature accumulation of adult-related transcripts in the primary leaves. Taken together, these results suggest that HYL1 controls the expression levels of miR156-targeted SPL genes and enables plants to undergo the juvenile phase, an important and critical step during plant development to ensure maximum growth and productivity.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Ligação a RNA
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Arabidopsis
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Regulação da Expressão Gênica no Desenvolvimento
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Proteínas de Arabidopsis
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MicroRNAs
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article